Enteric methane mitigation by using seaweed Eucheuma cottonii

Abstract

Methane is one of greenhouse gasses cause global climate change. Sources of methane emitted by livestock are from enteric fermentation during feed digestion in the rumen of ruminant animals and from manure of ruminant and non ruminant. Methane enteric contributes the largest portion of total gas emitted by livestock. Therefore, mitigation strategy of enteric methane production is become the important issue. The objective of this study was to determine the effect of Eucheuma cottonii (EC) seaweed added to basal diet on enteric methane production and fermentation kinetics by using in vitro method. Three level of EC were added to basal diet of Elephant Grass (EG), they were P0 = EG+ 0% EC; P1 = EG + 4% EC; P2 = EG + 8% EC; dan P3 = EG + 12% EC. All treatment was replicate five times. Variables measured were total and methane gas produced, dry matter and organic matter digestibility, pH, and ammonia concentration; rumen protozoa and bacterial population. The data obtained were analyzed using ANOVA and continued with Tukey test. The results showed that increasing level of EC on EG followed by declining methane gas produced by 7.66% ; 9.93%; and 16.74%, respectively (P<0.01); increased total bacteria population up to 169.7%, reduced protozoa population up to 69.2%; increased dry matter and organic matter digestibility (P<0.01). It is concluded that supplementation of E. cottonii on elephant grass basal diet on dose level of 4%, 8% and 12% reduced CH4 production as well as increased digestibility of the feed. The best level of E. cottonii supplementation in reducing CH4 production was 12% with can give reduction effect on CH4 up to 16.74% and increasing on digestibility up to 11.17%.